A value bridge (or EBITDA bridge) decomposes the total value created between entry and exit into its distinct sources: revenue growth, margin expansion, change in the valuation multiple, and debt paydown. It shows, quantitatively, where a return actually came from.
The purpose of the bridge is to keep everyone honest about which gains were earned and which were structural. It prevents crediting operating execution for value that was really produced by leverage or by a rising market multiple. A disciplined value bridge separates operating performance from financial and market effects, which matters both for underwriting the next deal and for judging the last one.